These tables compare features of multimedia container formats, most often used for storing or streaming digital video or digital audio content. To see which multimedia players support which container format, look at comparison of media players.
General information
Format | Filename extension | Owner or creator | Initial release | License |
VBR audio | VFR | Hardware players | Streaming |
Metadata |
Chapters | Interactive menus | 3D |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Matroska | .mkv, .mk3d |
CoreCodec |
2002-12 | Freely licensed |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Planned |
Yes |
MPEG-4 Part 14 (MP4) | .mp4, .m4v |
MPEG | 2001-10 | Patent encumbered |
Yes | Yes | Yes | Yes | Yes | Not standard |
Yes | Only at video format level |
QuickTime File Format (QTFF) | .mov, .qt | Apple Inc. | 1991-12 | Proprietary |
Yes | Yes | Yes | Yes | Yes | Yes | Yes | Not standard |
Advanced Systems Format (ASF) | .asf, .wmv |
Microsoft | 1996-09 | Royalties on codecs |
Yes | Yes | Yes | Yes |
Yes | Yes | No | Not standard |
Audio Video Interleave (AVI) | .avi | Microsoft | 1992-11 | Proprietary |
Yes |
Yes |
Yes | No | Yes | Needs alterations | No | No |
Material Exchange Format (MXF) | .mxf | SMPTE | 2004-09 | Patent-free |
Yes | Yes | No | Yes |
Yes | No | No | Yes |
MPEG program stream (PS) | .m2p, .ps |
MPEG | 1993-08 | Patent-free |
Yes | Yes |
Yes | No | No | No | No | No |
MPEG transport stream (TS) | .ts, .tsv |
MPEG | 1995-07 | Patent-free |
Yes | Yes | Yes | Yes | No | No | No | No |
BDAV MPEG-2 transport stream (M2TS) | .m2ts, .mts | BDA | 2004-08 | Patent encumbered | Yes | Yes | Yes | With DVB |
Needs multiple files |
Needs multiple files |
Yes | Needs multiple files |
Video Object (VOB) | .vob | DVD Forum | 1996-11 | Patent encumbered | Yes | Yes | Yes | No | No | Needs multiple files |
Needs multiple files |
No |
Enhanced VOB (EVO) | .evo | DVD Forum | 2006-03 | Patent encumbered |
Yes | Yes | Yes | No | No | Needs multiple files |
Yes | No |
3GPP (3GP) | .3gp | 3GPP | 2003-04 | Patent encumbered | Yes | Yes | Yes | Yes |
Yes | No | No | No |
3GPP2 (3G2) | .3g2 | 3GPP2 | 2004-01 | Patent encumbered | Yes | Yes | Yes | Yes | Yes | No | No | No |
Flash Video (F4V) | .f4v |
Adobe Inc. | 2007-12 | Patent encumbered | Yes | Yes | Yes | Yes | Yes | Yes |
No | No |
Flash Video (FLV) | .flv | Adobe Inc. | 2003-09 | Proprietary |
Yes |
Yes | Yes | With RTMP | Yes | Yes |
No | No |
Ogg | .ogv, .ogx |
Xiph.Org | 2003-05 | Open source |
Yes | Yes | Yes | Yes |
Yes |
As Vorbis comments |
No | No |
WebM | .webm | 2010-05 | Royalty-free |
Yes | Yes | Yes | Yes | Yes |
Yes |
No |
Yes | |
RealMedia Variable Bitrate (RMVB) | .rmvb | RealNetworks | 2003 | Proprietary | Yes | Yes | Yes | Yes | Yes |
No | No | No |
DivX Media Format (DMF) | .divx | DivX, Inc. | 2005-06 | Proprietary | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No |
- ↑ Indicates if the container can be used for a container bitstream, for example, for use as an RTP payload format. Some technologies, such as WebRTC, do not use any container formats for streaming. Some use fragmented MP4 (fMP4) or MPEG-TS segment files, such as HLS and MPEG-DASH.[2]
- ↑ Tags.
- ↑ Container format level.
- ↑ Also
.mka
for content that is primarily audio or.mks
for subtitles only.[4] - ↑ Although CoreCodec, Inc. holds the copyrights and trademarks for the Matroska specification, the specifications are open to everybody. The source code of the libraries developed by the Matroska team is licensed under the LGPL and BSD licenses.
- ↑ Anyone can use it or modify it for their own needs without paying any license or patents.[5][6]
- 1 2 Matroska is designed to store VBR and VFR content.[7]
- ↑ Companies producing Matroska-supporting hardware include Asus,[8] OPPO Digital,[9] Samsung,[10] and LG[11]
- ↑ Matroska can be streamed over HTTP and RTP/RTSP, through it is not meant to be streamed over RTP, as the two have duplicate features.[12]
- ↑ Also
.m4a
,.m4b
or.m4p
for audio-only content. - ↑ There are two popular representations: text track (QuickTime), and userdata atom (Nero).[18][19]
- ↑ Also
.wma
for audio-only content. - ↑ License required from manufacturers or developers of codecs, but no license fees for the distribution of content.[21]
- ↑ ACM cannot handle VBR audio streams in AVI files. Thus, software using ACM to read audio from AVI files will not be able to handle VBR audio streams correctly, even though such files are compliant to the AVI file specification. This is a limitation of the ACM, not of the AVI file format.
- ↑ Although AVI is not designed for variable framerates, it is possible to use them without creating a non-standard file by using 0-byte chunks for skipped frames. However, it requires the framerate to be set to the least common multiple of all framerates used, and produces slight overhead compared to true VFR.
- 1 2 The following extensions are also often used for an MPEG program or a transport stream:
.mpg
,.mpeg
,.mpv
,.m1v
; also.mpa
,.mp3
,.mp2
,.mp1
,.m2a
or.m1a
for audio-only content. - ↑ MPEG-2 Part 1 specification,[27] p. 64, sec. 2.6.3.
- ↑ Also
.tsa
for audio-only content. - ↑ Blu-ray adopts a specific file structure. Simple title metadata are stored in the
/BMDV/index.bdmv
file. - ↑ Blu-ray adopts a specific file structure. Chapters require a companion
.mpls
file in the/BDMV/PLAYLIST/
directory. - ↑ Blu-ray 3D adopts a specific file structure to encode stereoscopic video. MVC stereoscopic data is in
.ssif
files in the/BDMV/STREAM/SSIF/
directory and require a respective base.m2ts
file. - 1 2 VOB adopts a specific file structure to encode DVD content. Chapters and menus require a companion
.ifo
file. - ↑ EVO adopts a specific file structure to encode HD DVD content. Chapters require companion
.xpl
file.[30] - ↑ Also
.f4a
,.f4b
and.f4p
for audio-only content. - ↑ Adobe Flash Video File Format Specification,[34] p. 1. SWF File Format Specification,[35] p. 188.
- ↑ Also
.oga
,.ogg
or.opus
for audio-only content.[36][37] - ↑ Chapters stored as Vorbis comments[41] are well supported by common tools such as FFmpeg and VLC.
- ↑ Some stereo modes are supported.[43]
Attachments (additional files, such as fonts for subtitles) are only supported in Matroska,[16] MP4 and QTFF. M2TS supports attachments as multiple files in a specific file structure: fonts for subtitles are in .otf
files in the /BDMV/AUXDATA/
directory.
Some common multimedia file formats are not completely distinct container formats. Some are containers for specific audio and video coding formats, such as WebM, a subset of Matroska. Some are combinations of common container formats and audio and video coding profiles, such as AVCHD and DivX formats. Although sometimes compared to DivX products, Xvid is neither a container format nor a video format, it is a software library that encodes video using specific coding profiles of the common MPEG-4 ASP video format. Those types of restrictions are intended to simplify the construction of multimedia recorders and players.
Video coding formats support
Format | Type | Initial release | License |
MKV | MP4 |
QTFF |
ASF |
AVI |
MXF | PS, TS |
M2TS | VOB | 3GP, 3G2 | F4V | FLV |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
MPEG-H HEVC (H.265) | Lossy or lossless | 2013-06 | Patent encumbered |
Yes |
Yes | Yes |
Yes | Yes | Yes |
Yes | No | No | Yes | No | No |
MPEG-4 AVC (H.264) | Lossy or lossless | 2004-08 | Patent encumbered |
Yes | Yes | Yes | Yes | Yes |
Yes | Yes |
Yes | No | Yes | Yes | Not standard |
AV1 | Lossy or lossless | 2018-03 | Patent claims | Beta |
Yes | No | No | No | No | Planned | No | No | No | No | No |
VP9 | Lossy or lossless | 2013-06 | Patent claims | Yes | Yes | No | Yes | Yes | No | No | No | No | No | No | No |
VP8 | Lossy or lossless | 2008-09 | Patent claims | Yes | Yes | No | Yes | Yes | No | No | No | No | No | No | No |
Dirac | Lossy or lossless | 2008-03 | Patent-free |
VCM |
No | Yes | No | Needs Dirac |
No | Private | No | No | No | No | No |
MVC | Stereoscopic | 2009-05 | Patent encumbered | Yes |
No | No | No | No | No |
No | No | No | Yes | No | No |
MPEG-1 Video | Lossy | 1993-08 | Expired patents |
Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No | No | No |
MPEG-2 Video | Lossy | 1996-05 | Expired patents | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | No | No | No |
MPEG-4 Visual | Lossy | 1999-12 | Patent encumbered |
Yes | Yes | First edition | Yes | Yes | Yes | Yes | Yes | No | Yes | Yes | Yes |
Microsoft MPEG4 V2 | Lossy | 2003 | Patent encumbered, proprietary | Yes | Not standard | Not standard | Yes | Yes | No | No | No | No | No | No | No |
VC-1 | Lossy | 2006-02 | Patent encumbered |
VCM |
Yes |
Yes | Yes | Yes | Yes | No | Yes | No | No | No | No |
H.263 | Lossy | 1996-03 | Patent encumbered |
No | Yes | Yes | Yes | Yes | No | No | No | No | Yes | Yes | No |
Theora | Lossy | 2004-06 | Free license |
Yes | No | No | No | Needs ffdshow | No | No | No | No | No | No | No |
Cinepak | Lossy | 1991 | Proprietary | Yes | No | Yes | No | Yes | No | No | No | No | No | No | No |
Sorenson | Lossy | 1998-03 | Proprietary | Yes | No | Versions 1 and 3 | No | Version 1 | No | No | No | No | No | No | Spark |
RealVideo | Lossy | 1997-02 | Proprietary | RV10, RV20, RV30, RV40 | RV60 | No | No | Not standard | No | No | No | No | No | No | No |
VP6 | Lossy | 2003-05 | Proprietary | No | No | No | No | Needs VP6 |
No | No | No | No | No | No | Yes |
DV | Intra-frame | 1995 | Proprietary | VCM |
DVCPRO HD | DV 25 | Yes | Yes | Yes |
No | No | No | No | No | No |
M-JPEG | Intra-frame | 1994-05 | Expired patents |
VCM |
Yes | Yes | Yes | Yes | No | No | No | No | No | No | No |
JPEG 2000 | Intra-frame | 2000 | Royalty-Free |
No | Yes | No | No | Not standard | Yes | No | No | No | No | No | No |
Apple ProRes | Intra-frame | 2007-04 | Proprietary | No | No | Yes |
No | No | Yes |
No | No | No | No | No | No |
HuffYUV | Lossless | 2000 | Open source | VCM |
No | No | No | Needs HuffYUV |
No | No | No | No | No | No | No |
YCbCr |
Not compressed | 1982 | Patent-free | Yes | SheerVideo | Yes | Yes | Yes | Yes |
No | No | No | No | No | No |
Other | Other | — | Varies | — | — | DVC Pro 50, Photo JPEG, Graphics, QuickTime Animation | — | Indeo | — | JPEG 2000, TICO | — | — | — | — | Screen Video |
- ↑ See the MPEG-2 Part 1 specification[27] and registered TS identifiers.[51]
- ↑ Adobe Flash Video File Format Specification,[34] p. 72, sec. E.4.3.1; p. 1. SWF File Format Specification,[35] Chapter 14: Video, pp. 204-218.
- ↑ HEVC is mentioned in the latest (07) draft of Matroska,[53] MKVToolNix and VLC already support it.[54]
- ↑ B-frames in an AVI file are a problem only for the ancient Video-for-Windows API, not for the AVI container itself.
- ↑ MVC is not covered by the latest iteration of the MXF standards.[62]
- ↑ MPEG, MXF, and SMPTE 381M,[63] pp. 201-219.
- ↑ DV, DVC Pro, and DVCam in MXF,[63] pp. 166-172.
- ↑ The digital YCbCr format is often informally called YUV, the analog format used as basis for it.
Some containers only support a restricted set of video formats:
- DMF only supports MPEG-4 Visual ASP with DivX profiles.
- EVO only supports MPEG-4 AVC, MPEG-1 Video, MPEG-2 Video and VC-1.
- Ogg only supports Theora, MNG, JNG,[lower-alpha 5] PNG[80] and Dirac.[81][82] Firefox supports VP9 and VP8 in Ogg.[83] VLC supports MPEG-2 Video, MPEG-4 Visual and VC-1 in Ogg.[84]
- RMVB only supports RealVideo versions RV30, RV40 and RV60.
- WebM only supports VP9 and VP8.[43] Support for AV1 is in development.[59]
Audio coding formats support
Format | Type | Initial release | License |
MKV | MP4 |
QTFF |
ASF |
AVI |
MXF | PS, TS |
M2TS | VOB |
3GP | 3G2 | F4V | FLV |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
AAC | Lossy | 1997-12 | Royalties on codecs |
Yes | Yes | Yes | AAC-LC, HE-AAC[87] | AAC-LC, HE-AAC |
Yes | Private | No | No | AAC-LC, HE-AAC | AAC-LC, HE-AAC v1 | Yes |
Yes |
MP3 | Lossy | 1991-12 | Expired patents |
Yes | Yes | MPEG-1 Audio | Yes | Yes |
Yes | Yes | No | No | No | No | Yes | Yes |
AC-3 | Lossy | 1991-02 | Expired patents | Yes | Yes |
Yes | Yes | Yes | Yes | Private | Yes | Private | No | No | No | No |
E-AC-3 | Lossy | 2005-02 | Patent encumbered | QuickTime |
Yes | Yes | Yes | No | No | No | Yes | No | No | No | No | No |
DTS | Lossy | 1993-06 | Proprietary | Yes | Yes | No | Yes | Yes | No | Private | Yes | Private | No | No | No | No |
WMA | Lossy | 1999-08 | Proprietary |
ACM |
No | No | Yes | Yes | No | No | No | No | No | No | No | No |
Opus | Lossy | 2012-09 | Royalty-free | Yes | Yes | Yes | Yes | Yes | No | Yes | No | No | No | No | No | No |
Vorbis | Lossy | 2000-05 | Open source[93] | Yes | Private | No | No | Tricky |
No | No | No | No | No | No | No | No |
MP2 | Lossy | 1991-12 | Patent-free |
Yes | Yes | No | Yes | Yes | Yes | Yes | No | Yes | No | No | No | No |
MP1 | Lossy | 1991-12 | Expired patents | Yes | Yes | No | Yes | Yes | Yes | Yes | No | No | No | No | No | No |
QDesign Music 1 and 2 | Lossy | 1998 | Proprietary | QuickTime |
No | Yes | No | No | No | No | No | No | No | No | No | No |
ATRAC3 | Lossy | 2000-09 | Proprietary | Yes | No | No | No | No | No | No | No | No | No | No | No | No |
FLAC | Lossless | 2001-07 | Open source | Yes | Yes | No | Yes | Yes | No | No | No | No | No | No | No | No |
ALAC | Lossless | 2004-04 | Open source | Yes | Yes | Yes | Yes | Yes | No | No | No | No | No | No | No | No |
WMA Lossless | Lossless | 2003-01 | Proprietary |
ACM |
No | No | Yes | Yes | No | No | No | No | No | No | No | No |
DTS-HD | Lossless | 2011-08 | Proprietary | Yes | Yes |
Yes | No | No | No | No | Yes | No | No | No | No | No |
Dolby TrueHD | Lossless | 2006-04 | Proprietary | Mature |
Yes | No | No | No | No | No | Yes | No | No | No | No | No |
MLP | Lossless | 1999-03 | Proprietary | No | Yes |
No | No | No | No | Private | No | Private | No | No | No | No |
ALS | Lossless | 2006-03 | Patent encumbered | No | Yes | No | No | No | No | Yes | No | No | No | No | No | No |
SLS | Lossless | 2006-06 | Patent encumbered | No | Yes | No | No | No | No | Yes | No | No | No | No | No | No |
LPCM | Not compressed | 1979 | Patent-free |
Yes | Yes | Yes | Yes | Yes | Yes | Private | Yes | Private | No | No | No | Yes |
A-law PCM | Not compressed | 1972-12 | Expired patents |
ACM |
No | Yes | No | Yes | Yes | No | No | No | No | No | No | Yes |
μ-law PCM | Not compressed | 1972-12 | Expired patents |
ACM |
No | Yes | Yes | Yes | No | No | No | No | No | No | No | Yes |
IEEE floating-point PCM | Not compressed | ≥1985 | Patent-free |
Yes | No | Yes | Yes | Yes | No | No | No | No | No | No | No | No |
Microsoft ADPCM | Not compressed | 1992-05 | Proprietary | ACM |
No | Yes | Yes |
Yes | No | No | No | No | No | No | No | No |
DV Audio | Not compressed | 1995 | Proprietary | No | Yes | Yes | No | No | Yes |
No | No | No | No | No | No | No |
AMR | Speech | 1999-06 | Patent encumbered | No | Yes | No | Yes | Yes | No | No | No | No | Yes | AMR-NB, AMR-WB | No | No |
G.728 | Speech | 1992-09 | Expired patents | No | No | No | No | Yes | No | No | No | No | No | No | No | No |
Speex | Speech | 2003-03 | Open source |
ACM |
No | No | No | No | No | No | No | No | No | No | No | Yes |
QCELP | Speech | 1994 | Proprietary | No | No | Yes | Yes | No | No | No | No | No | No | 13K | No | No |
Other | Other | — | Varies | Musepack, WavPack, TTA, any format supported by ACM | — | IMA 4:1, non-IEEE floating-point PCM, integer PCM | Microsoft GSM 6.10 | G.721, G.722, G.723, G.726, G.729a, CVSD, ATRAC1, Dolby AC-2 | — | — | — | — | EVS | EVRC, EVRC-B, EVRC-WB, SMV, VMR-WB | — | Asao, SWF ADPCM[101] |
Obsolete | Other | — | Varies | — | — | MACE 3:1, MACE 6:1 | — | Truespeech, many others | — | — | — | — | — | — | — | — |
- ↑ Adobe Flash Video File Format Specification,[34] p. 70, sec. E.4.3.2; p. 1. SWF File Format Specification,[35] Chapter 11: Sounds, pp. 177-192.
- ↑ License required from manufacturers or developers of codecs, but no license fees for the distribution of content.[86]
- 1 2 Setting
dwSampleSize
to 0 in the stream headers triggers VBR stream seeking[89] allowing VBR audio formats in AVI.[90] - ↑ Adobe Flash Video File Format Specification,[34] pp. 7-8, sec. 1.8.
- 1 2 Matroska can support some codecs privately when wrapped in a QuickTime data structure.[72]
- ↑ Vorbis is not officially supported in AVI. While it can technically be muxed into AVI using FFmpeg, Nandub and AVI-Mux GUI[94] many sources report trouble playing back the resulting files,[95] which are incompatible with existing Vorbis decoders for DirectShow and ACM, occasionally causing desynchronization when seeking.
- ↑ Proprietary tools.[96]
- ↑ Dolby TrueHD is supported by common tools such as MKVToolNix and VLC.
- ↑ Special case of LPCM.[98]
Some containers only support a restricted set of audio formats:
- DMF only supports MP3, AC-3, DTS and LPCM.
- EVO only supports MP3, AC-3, E-AC-3, DTS, MP2, MP1, DTS-HD, Dolby TrueHD, MLP and LPCM.
- Ogg only supports Opus, Vorbis, FLAC, A-law PCM, μ-law PCM, IEEE floating-point PCM, Speex and CELT.[lower-alpha 5] OGMtools supports MP3 and AC-3 in Ogg.[102]
- RMVB only supports AC-3, ATRAC3, G.728, AAC-LC, HE-AAC v1, IS-54, Cook Codec, Sipro Lab, ACELP-NET and RealAudio Lossless.
- WebM only supports Opus and Vorbis.[43]
Audio-only content can sometimes be placed in a simpler audio-only container, such as Native FLAC for FLAC[103] and ADTS for AAC.
Subtitle formats support
Format | Type | Initial release | License |
MKV |
MP4 | QTFF |
ASF |
AVI |
MXF |
PS, TS |
M2TS | VOB | 3GP, 3G2 | F4V | FLV |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
SubRip |
Formatted text | 2000-03 | Open source | Yes |
As TTXT |
As TTXT |
As SAMI |
Needs alterations |
As SMPTE-TT | No | No | No | As TTXT |
As TTXT |
No |
WebVTT | Formatted text | 2010-08 | Open source | Yes |
Yes |
As TTXT |
No | No | As SMPTE-TT | No | No | No | As TTXT |
As TTXT |
Using ActionScript |
ASS, SSA | Formatted text | 1996 | Open source | Yes |
No | No | No | Needs alterations |
As SMPTE-TT | No | No | No | No | No | No |
TTXT |
XML | 2006-04 | Patent encumbered | No |
Yes | Yes |
No | No | No | No | No | No | Yes | Yes |
No |
USF | XML | 2002-11 | Proprietary | Planned | No | No | No | Needs alterations | No | No | No | No | No | No | No |
SAMI | HTML | 1998-06 | Proprietary | No | No | No | Yes | Needs alterations | As SMPTE-TT | No | No | No | No | No | No |
VobSub | Picture | 2001 | Patent encumbered | Mature |
Yes | Not standard | No | Needs alterations | No | No | As PGS |
Yes | No | No | No |
PGS |
Picture | 2006-03 | Patent encumbered | Mature |
As VobSub |
No | No | No | No | No | Blu-ray | As VobSub |
No | No | No |
DVB-SUB |
Picture | 1997-09 | Patent encumbered | Mature |
No | No | No | No | Yes |
Yes | No | No | No | No | No |
Ogg Kate |
Picture or formatted text | 2008-03 | Open source | Mature |
No | No | No | No | No | No | No | No | No | No | No |
TextST |
Text stream | 2006-03 | Patent encumbered | Beta | No | No | No | No | No | No | Yes | No | No | No | No |
MicroDVD | Plain text | 2000-03 | Proprietary | No | No | No | No | Needs alterations | No | No | No | No | No | No | No |
Other | Other | — | Varies | Generic bitmap images, generic plain text |
BIFS | Quicktime SMIL, EIA-608, CTA-708 | — | XSUB |
SMPTE-TT, EBU-TT |
CTA-708 | — | — | — | — | — |
- ↑ AVI is not designed to embed subtitles, requiring changes to the format and third party tools such as DirectVobSub[105] and VLC.
- ↑ SMPTE standardized the format for text subtitles in MXF[106][107][108] without a reference software implementation, leaving it to independent developers.[109]
- ↑ SubRip can be converted losslessly to and from native subtitle formats of several containers, and this conversion is supported by many common tools.
- ↑ Requires tools that are not officially related to the container format.[109]
- ↑ Loading subtitles with ActionScript[114] may be restricted to the official Adobe Flash Player.
- ↑ TTXT is often called MPEG-4 Timed Text (MP4TT, MP4-TT) or 3GPP Timed Text (3GPP-TT, tx3g).
- ↑ MPEG-4 Timed Text subtitles aren't supported in Matroska according to developer of MKVToolNix.[116]
- 1 2 3 4 VobSub, PGS, DVB-SUB and Ogg Kate are well supported by common tools such as MKVToolNix and VLC. The storage format is specified,[53] but the specification is not officially approved yet.
- 1 2 3 Requires tools that are not officially related to the container format.[117]
- 1 2 HDMV PGS and TextST subtitles are used on HD DVD and Blu-ray.
- ↑ Needs alterations to the container.
[121][122]
Some containers only support a restricted set of subtitle formats:
- DMF only supports XSUB.
- EVO only supports HD DVD PGS.
- Ogg only supports Ogg Kate and CMML.[lower-alpha 5] SubRip can be converted losslessly to Ogg Kate.[124] Ogg Writ[125] is well supported in Ogg in common tools such as OGMtools[102] and VLC, but there's no intention to turn its draft into a fully supported specification. Xiph recommends using Kate for subtitles.[126] MicroDVD can be converted to Ogg Writ.
- RMVB only supports RealText. SMIL can be partially converted to RealText.
- WebM only supports WebVTT.[43] SubRip can be converted losslessly to WebVTT.
Converting image subtitles to text formats is possible using third-party tools[127] but relies on optical character recognition, which is not perfectly accurate and can at best extract basic formatting. Conversion of text to images is possible while preserving content and style. Round-trip format conversion between text formats may not be possible without losing some formatting features.
Overhead
Multimedia containers interleave data in media streams to enable efficient playback using fewer computational resources, such as time spent reading from the storage drive, memory needed to buffer selected media streams, and time spent decoding when seeking to a different position in time. In this sense, muxing overhead is the control information added by the container to carry interleaved streams. A smaller overhead results in a smaller file when carrying the same streams with the same data. Overhead is affected by the total number of packets and by the size of stream packet headers. In high bitrate encodings, the content payload is usually large enough to make the overhead data relatively insignificant, but in low bitrate encodings, the inefficiency of the overhead can significantly affect the resulting file size if the container uses large stream packet headers or a large number of packets.
In general, Matroska[128] requires the least overhead, followed by MP4, AVI and Ogg.[129]
See also
Notes
- 1 2 3 4 Indicates whether the standard is open or proprietary, patent-free or encumbered, whether royalty payments are required for streaming and codec implementation, and may indicate the availability of free tools for it.[1]
- 1 2 3 See the QuickTime File Format Specification[46] and MP4RA's Entry Codes Registered for QuickTime.[45]
- 1 2 AVI officially supports all codecs in the Media Foundation[48][47] which is an evolution of VCM and ACM, both of which are now obsolete. Some older codecs used to be officially supported,[49] and there are many known non-standard third-party extensions.[50]
- 1 2 3 4 5 6 7 8 9 10 11 Matroska can support some codecs when wrapped in two specific Video for Windows data structures, VCM and ACM,[72] but support outside Windows may be limited.[72]
- 1 2 3 Xiph has standardized the support for codecs in Ogg,[36] but added support for more codecs afterwards.[79][37]
References
- ↑ Multimedia format issues for CWS task forces (PDF). Eighth Session of the Committee on WIPO Standards (CWS). Geneva: World Intellectual Property Organization. 23 October 2020. CWS/8/ITEM 3. Archived (PDF) from the original on 3 December 2021. Retrieved 3 December 2021.
- ↑ Siglin T (8 April 2020). "Understanding How to Acquire and Deliver Live Streams". Wowza Media Systems. Archived from the original on 8 December 2021. Retrieved 8 December 2021.
- ↑ Gavrilov K (2017). "Stereoscopic Formats". sView (Guide). Archived from the original on 26 February 2021. Retrieved 26 July 2019.
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I figured these 4 files are needed to accomplish the task: the .xpl file where the chapter name and timestamp are located...
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With Final Cut Pro 10.3 or later, you can also export ProRes files inside an MXF metadata wrapper instead of exporting .mov files. ... A ProRes-encoded bitstream, typically in the form of a .mov file
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Well, MPEG-4 Timed Text subtitles are standard for the MP4 container format, they just aren't supported in anything else out there. ...
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: CS1 maint: location missing publisher (link) - ↑ OggWrit (Specification). Xiph.Org Foundation. 10 November 2007. Retrieved 27 July 2019.
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